Hypothesis of monoamines in Depression

1)Reduction in serotonin levels (follow stressful events)-failure to regulate dopamine &noradrenaline-disrupts moos&activity levels.2)Disruption of monoamines levels-High level of enzymes that breaks down monoamines-reduce their actions&disrupts the passage of information around the brain.

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Dopamine in schizophrenia

1)Excess of dopamine in centres of the brain responsible for speech may cause hallucinations of voices.2)Low activity of dopamine in pre frontal cortex(thinking&decision making) May explain symptoms such as apathy and incoherent thought or speech.

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Genetic explanations?

-Genes are sections of DNA that contains instructions for producing physical structures including the brain, neurotransmitters &enzymes that breaths them down.-it can influence the nature of physical structures of chemical level in the nervous system.

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Genetic Vulnerability in Depression

-Stressful life events-Depression.Genes may effect how resilient &vulnerable we are.Eg; serotonin transporter gene comes in 3 (long-long, long-short, short-short), short-short leads to inefficient serotonin production. Less resilient to the effects is stress &are more vulnerable to respond to stress with depression.

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Genetic vulnerability in schizophrenia

-Can be genetically influenced-family member.-polygenic- influenced by over 100 genes-aetiologically heterogeneous- different combination of factors can lead to similar symptoms